Simulated Driving and Attention of Repeat Users of MDMA and THC Compared with THC Users and Non-Drug-Using Controls
Caroline T. J. Lamers, Matthew Rizzo, Antoine Bechara, Jan Ramaekers
Transportation Research Record: Journal of the Transportation Research Board 2006 DOI: 10.1177/0361198106196900107 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational comparative study Peer reviewed |
|---|---|
| Sample size | 42 |
| Population | Abstinent MDMA and marijuana users, marijuana-only users, and non-drug-using age-matched controls |
| Topics | Cannabis MDMA |
| Key findings | MDMA/THC users entered a simulated collision at 42 mph versus 26 mph for controls, and THC users reduced speed 7 mph less than controls when passing a parked car. Processing speed and attention did not differ between groups, suggesting executive function impairments. Because collision speed did not differ between MDMA/THC and THC users, a specific role of MDMA remains to be established. |
Abstract
The aim of the study is to assess if cognitive impairments in abstinent users of methylenedioxymethamphetamine (MDMA) are due to repeated use of MDMA or concurrent drugs of abuse and how these impairments interfere with key activities of daily life such as automobile driving. Simulated driving performance and attention of 12 users of MDMA and marijuana [tetrahydrocannabinol (THC)] (MDMA/THC), 15 THC users, and 15 non-drug-using, age-matched controls were compared. THC users’ mean speed reduction in response to passing a car parked on the shoulder of the road was 7 mph (11.3 km/h) less than that of controls. Compared with non-drug-using controls, the MDMA/THC users were less able to mitigate the effects of an illegal intersection incursion by another vehicle and entered the collision at a higher speed (42 versus 26 mph). In real life, this 16-mph (26-km/h) difference would increase the likelihood of injuring parties in both colliding vehicles. Processing speed and attention did not differ between groups; this suggests that the lower speed reduction in the MDMA/THC users was more likely due to executive function impairments (incorrect situation interpretation and awareness) than to reduced processing speed. In conclusion, compared with non–drug users, MDMA/THC users may be at a greater risk for driver performance errors that lead to crashes. Because collision speed did not differ between MDMA/THC users and THC users, a specific role of MDMA as opposed to THC toxicity in driving performance impairment remains to be established.
Comparable studies
Other observational and cohort studies on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| High-potency cannabis and the risk of psychosis People with first episode of psychosis and healthy controls from the local population | 2009 | Case-control study | n = 454 |
| Ayahuasca-Assisted Therapy for Addiction: Results from a Preliminary Observational Study in Canada Rural aboriginal population | 2013 | Observational study | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| Continued cannabis use and risk of incidence and persistence of psychotic symptoms: 10 year follow-up cohort study Individuals from the general population in Germany aged 14-24 at baseline | 2011 | Observational cohort | n = 1,923 |
| Cannabis-induced psychosis and subsequent schizophrenia-spectrum disorders: follow-up study of 535 incident cases Patients treated for cannabis-induced psychotic symptoms in Denmark between 1994 and... | 2005 | Observational cohort | n = 535 |
Citations in the library
Cited by 2
Cites 12
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- Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Journal of Neurology, Neurosurgery, and Psychiatry June 1, 2000
- Cognitive performance in recreational users of MDMA or 'ecstasy': evidence for memory deficits Journal of Psychopharmacology 1998
- (±)3,4-Methylenedioxymethamphetamine (‘Ecstasy’)-Induced Serotonin Neurotoxicity: Clinical Studies Neuropsychobiology 2000
- RETRACTED: Severe Dopaminergic Neurotoxicity in Primates After a Common Recreational Dose Regimen of MDMA ("Ecstasy") Science September 27, 2002
and 7 more in the library